This invention relates to pressure regulating devices, and relates more particularly to an improved valve for limiting maximum pressure in a fluid carrying duct without utilization of a poppet-seal configuration.
Pressure regulators such as a pneumatic bleed off valve which functions to limit maximum pressure and/or maintain a constant pressure in a fluid carrying duct, are many times subject to premature failure due to erosion, wear, or deterioration at the valving surface. For instance, high pressure valves of the type referred to normally incorporate a poppet seat arrangement which includes a spring loaded poppet that is urged into direct, sealing contact with a seat. To reduce wear and deterioration of such seat, it has been proposed previously to utilize an elastomeric or other somewhat deformable material on the seat to insure good sealing action. Regardless of the material constituting the seat, it is common that malfunction of the valve can in many cases be traced to the direct contact between the valve seat and the poppet seat. Sliding type valves of the prior art inherently require extremely expensive machining and/or treatment to obtain close tolerances and effective sealing between sliding rather than impacting surfaces.
Exemplarly of prior arrangements are the structures shown in U.S. Pat. Nos. 2,416,855; 3,103,949; 3,282,288; 3,690,344; and 3,926,211, none of which contemplate the improvements and advantages of the present invention.